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1.
《International Journal of Hydrogen Energy》2022,47(65):28152-28164
The combustion characteristics of ammonia/methanol mixtures were investigated numerically in this study. Methanol has a dramatic promotive effect on the laminar burning velocity (LBV) of ammonia. Three mechanisms from literature and another four self-developed mechanisms constructed in this study were evaluated using the measured laminar burning velocities of ammonia/methanol mixtures from Wang et al. (Combust.Flame. 2021). Generally, none of the selected mechanisms can precisely predict the measured laminar burning velocities at all conditions. Aiming to develop a simplified and reliable mechanism for ammonia/methanol mixtures, the constructed mechanism utilized NUI Galway mechanism (Combust.Flame. 2016) as methanol sub-mechanism and the Otomo mechanism (Int. J. Hydrogen. Energy. 2018) as ammonia sub-mechanism was optimized and reduced. The reduced mechanism entitled ‘DNO-NH3’, can accurately reproduce the measured laminar burning velocities of ammonia/methanol mixtures under all conditions. A reaction path analysis of the ammonia/methanol mixtures based on the DNO-NH3 mechanism shows that methanol is not directly involved in ammonia oxidation, instead, the produced methyl radicals from methanol oxidization contribute to the dehydrogenation of ammonia. Besides, NOx emission analysis demonstrates that 60% methanol addition results in the highest NOx emissions. The most important reactions dominating the NOx consumption and production are identified in this study. 相似文献
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Industrial-grade cardanol and 2-mercaptoethanol were reacted to generate hydroxyl-functionalized cardanol by UV, free-radical-initiated thiol-ene coupling between the double bond moieties of the cardanol long carbon side chain and thiol functional groups. The average hydroxyl number of the hydroxyl-functionalized cardanol was controlled by reaction time, with the hydroxyl values of this ranging within 168–201 mg KOH g−1. This cardanol was then used as a polyol to prepare cardanol-based polyurethane with hexamethylene diisocyanate and a NCO/OH ratio of 1. To compare the effect of cardanol-based polyols with the properties of cardanol-based polyurethane, cardanol modified with 10-undecylenate was used as a raw material to prepare cardanol-based polyols, including the long carbon chain of 10-undecylenate. All properties were examined, and data revealed that cardanol-based polyols including this long carbon chain can improve the hydrophobic and mechanic properties of the cardanol-based polyurethane. 相似文献
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《Materials Letters》2007,61(11-12):2164-2166
By radiating a linear polyethylenimine–HAuCl4 aqueous solution with natural sunlight, we obtained polyelectrolyte-protected gold nanoparticles, and the size of such gold nanoparticles can be controlled by varying the molar ratio of polyelectrolyte to gold. 相似文献
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文中提出了一种应用RBF神经网络对标准IMM算法中的卡尔曼滤波结果进行校正的方法。网络输人为预测误差、卡尔曼增益以及测量值与估计值之差.网络输出反映了由于目标机动所带来的滤波误差.将网络输出结果和直接由卡尔曼滤波求解得到的结果相加.可以得到更为准确的滤波值。同时.在网络的学习算法中.在网络权值矩阵的修正公式中增加了反映滤波残差的调整项.若卡尔曼滤波的残差较大,网络调整权值的幅度也相应增大。仿真结果表明.在目标发生机动转弯处.校正后的IMM算法的跟踪误差要明显小于标准IMM算法的跟踪误差.跟踪精度较高。 相似文献
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《钢铁研究学报(英文版)》2006
The time dependence of magnetization is usually expressed as M(t)=M0-SInt [see Proc. Phys. Soc. 62, 562 (1949)] for magnetic viscosity experiments. Considering magnetic interaction during the thermal activation process, a form as M(t)=M0-SIn(t+t0) is deduced. The dipolar interaction and exchange coupling in a magnet can lead to positive and nonpositive t0, respectively. In the experiments of the magnetic viscosity for nanocrystalline Pr2Fe14B ribbons, the existence of positive t0 is confirmed. 相似文献
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OLAM(On-line Analytical Mining)是当前的热点技术,是融合了联机分析处理(OLAP)和数据挖掘(Data Mining)的一种新的数据挖掘技术。本文主要研究数据仓库中OLAP,On-line Analytical Processing和数据挖掘技术,这两个技术是商业智能中的核心技术和主要内容,在两者的基础上引入OLAM的概念,并阐述其基本原理和核心技术。基于微软的SQL Server平台,为一个商业案例建立数据仓库,利用Analysis Services服务,建立销售分析的多维数据集,利用OLAM的基本模型实现OLAP和聚类挖掘技术的结合,借助两者的各自优势,得到很好的客户聚类分析结果。 相似文献
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